Computer controlled ink jet printing

ABSTRACT

Variable alpha/numeric data is printed by a non-impact printing system in registered and aligned relationship with fixed data printed by a master plate cylinder on a moving web at press speeds. A programmed computer provides coded data representative of the variable data in a selected multiple line message format. Character timing signals are generated in response to the coded data and command signals from the computer represent the sequential position of the alpha/numeric data in the multiple line message format. The timing signals are automatically adjusted to accommodate different web speeds and variable form depths by an electrical top of form pulse occurring prior to the mechanical top of form of the master cylinder for each revolution thereof corrected by pulses, the rate of which is dependent on the speed of the web. The variable alpha/numeric data is printed by using the character timing signals to independently control the projection of ink droplet streams from a plurality of ink jet nozzles onto the moving web.

United States Patent Macllvaine Oct. 14, 1975 COMPUTER CONTROLLED INKJET IBM Tech. Discl. Bul1., Vol. 14, No. 9, Feb., 1972, p.

PRINTING 2796, Variable Delay for Ink Jet Printer. 75 Inventor: DonaldA. M n Lockpon [BM Tech. DlSCl. Bul1., V01. 11, NO. 12, May, 1969, NYpp. 1736-1737, Electrostatic Ink Deflection Bar Code Printer." [73]Assignee: Moore Business Forms, Inc.,

Fans Primary ExaminerE. H. Eickholt [22] Filed; Se t, 4, 1973 Attorney,Agent, or Firm watson, Cole, Grindle &

[21] Appl. N0.: 394,208

[52] US. Cl 101/426; 101/52; 197/1 R; 340/l72.5; 346/75 [51] Int. C1.B41L 47/46 [58] Field of Search 101/47, 52, l R, 426, 92, 101/93 C, DIG.l3; 197/1 R; 346/75, 1 R; 226/1, 2, 9, 47; 340/1725, 203, 340/205, 206,259

[56] References Cited UNITED STATES PATENTS 3,285,169 11/1966 Hartwig101/426 X 3,473,074 10/1969 J0ann0u..... l01/D1G. 13 3,540,372 11/1970Chambon... 101/92 3,576,367 4/1971 Sable IUI/DIG. 13 3,588,906 6/1971Van Brimer et a1. 346/75 X 3,708,050 l/l973 McCarthy .lr. 101/93 C X3,769,624 10/1973 Lee et a1 1 346/75 X 3,787,882 l/l974 Fillmore et a1.346/75 3,789,969 2/1974 Howard et a]. 197/1 R 3,797,022 3/1974 Beam ctal 346/75 3,803,628 4/1974 Van Brimcr et a1. 346/75 X OTHER PUBLICATIONSIBM Tech. Discl. Bul1., Vol. 12, No. 12, May, 1970, pp. 2202-2204,Non-Impact Printer Logical Design."

Watson 1 ABSTRACT Variable alpha/numeric data is printed by a non impactprinting system in registered and aligned relationship with fixed dataprinted by a master plate cylinder on a moving web at press speeds. Aprogrammed computer provides coded data representative of the variabledata in a selected multiple line message format. Character timingsignals are generated in response to the coded data and command signalsfrom the computer represent the sequential position of the alpha/numericdata in the multiple line message format. The timing signals areautomatically adjusted to accommodate different web speeds and variableform depths by an electrical top of form pulse occurring prior to themechanical top of form of the master cylinder for each revolutionthereof corrected by pulses, the rate of which is dependent on the speedof the web. The variable alpha/numeric data is printed by using thecharacter timing signals to independently control the projection of inkdroplet streams from a plurality of ink jet nozzles onto the moving web.

19 Claims, 26 Drawing Figures a? 5,2 34 r can FORMS) OPERATOR PosmouSYSTEM CONTROL mo e DlSPLAY gg 31o HO'LILE. ELECTRONICS .Y MAggt r-gtcMA'fllnfi GENERATOQ UN" 0 COMPUTER fia g gf /1, CONVERSION 55 24201 31NOZZLE maven m ggm '9 VIDEO mpuneta unit 1 Comm E F t g'l l tl DATA\NPUT sequencme PHASlNG DtzoPueT sensor:

NOZZLES US. Patent Oct. 14, 1975 Sheet 1 of 15 3,911,818

Her 2 32 =57 NK fig, cm FORMS em OPERATOR Po sson CONTROL mspuw $52 3)oNO'L'ZLE ELECTQONKS 1 MAeNEnc 1 Mmm GENERATOR TAPE compuwesz D coNvEwoNmm 0 COMPUTER \NTERFAQE A \NPUT NOZZLE DQ\\/ER MAGNHC 2g vxoeo mPLmERTAPE 7 we VOLTAGE UNT 0m CONTROL Mme DEFLECHON DATA mpuw SEQUENCNGPHASMG DROPLET semen uozzues US. Patent Oct. 14,1975 SheetZof 153,911,818

L A K W H 1 E US. Patent 001. 14, 1975 Sheet 3 of 15 3,911,818

U.S. Patent 0a. 14, 1975 Sheet 7 of 15 3,911,818

TUE ZONE Sow w 05 fax w .r

, ukm a dma P255 "65 mm @I :83

O J m XYdD w wE 20am 5 $2262.5 7. WJNHOZ OF US. Patent 01.14, 1975 Sheet8 0f15 3,911,818

H6: 5 TO 1 161.?

El FROM F16 G u u M W 6 1 M 2 H v F 5 Q n R 1 1 835 P 4 P MD w. W p oA 1. y 4 N U A 1 2w R m k w s m UQ 3L ma 1 V1. D v 0. Wm 8 1C mm we m EH A mo. J a K L 1% V M 0 m a v m2 1 U.S. Patent Oct. 14, 1975 Sheet 100f15 3,911,818

o, m. a,

w mm 0 mm vaw US. Patent Oct. 14,1975 Jheet n 0f15 3,911,818

FORM DEPTH 1,15,4-

MECHANKAL TOP OF FORM V1 M 7.500 SUTS F/a 13 ELECT mc '10? OF FORM FORMDEPTH 4- FORM DEPTH 4 vow DEPTH FORM new 3 k/ FORM DEPTH '2, 4

PIUNT REQUEST PR1 NT READY 1- 1 l I l H6L STRI L n ,1 r1 1 lfl 1! I F 1i i I 1 V53 1 l I 1 1: 1

tr 1 1 1 I ll ME VMZY1NG WVI'H PRESS SPEED k CLOCK US Patent Oct. 14,1975 Sheet 14 of 15 3,911,818

SUPPLY AND BLEED SOLENEND ASSEMBLY \NK SUPPLY MIMMFOLD \Q z I 1 L 1 F QT r l 1 1m;

. 1 L: L :Z 1' 1 Tlr "VACUUM MAmFoLo WEB COMPUTER CONTROLLED INK JETPRINTING This invention relates to both apparatus and methods forcomputer controlled printing presses and more specifically to suchapparatus using the principle of nonimpact ink jet printing whereby thevariable message data can be imprinted on paper along with the printingof fixed data at press speeds. The COMPURITE printing system disclosedherein represents a combining of business forms printing press equipmentand computer outputs for the simultaneous printing of a form (or directmail advertising piece) and the imprinting of variable data. Thevariable data may be an address or other variable information availableon the magnetic tape.

The COMPURITE system disclosed herein represents apparatus and methodintroducing a capability of printing at a maximum speed of 1,375characters per second. At such speed variable information composed of 5X 7 dot matrix characters may be printed on a web of paper moving atmaximum press speeds. The COM- PURITE apparatus disclosed herein iscapable of being installed on printing presses without significantlyreducing the efficiency of the existing production equipment. Forexample, the COMPURITE system provides significant advantages because ofits modular characteristics which enhances its portability. it may beinstalled on multiprinter flexographic printing presses for producing awide variety of products and sizes.

Flexography is a rotary, relief printing process employing fast drying,evaporating, solvent inks and usually flexible rubber printing plates.It is this ink distribution and transfer system made mandatory by suchinks, the comparatively inexpensive printing plates, and the greatadvantage of quick and simple roller cleanup and press setup in changingfrom one job to the next, which sets flexography apart from therun-of-the-mill letterpress printing and makes it especially adaptableto high speed, low cost, in-line printing with converting machinery.Within reasonable limits, changes in size of the printing repeat can beaccomplished economically and with insignificant waste. By mountingplates on printing cylinders of different circumferences and changingthe spacing across the cylinders, size variations can be made in boththe length and width. This interchangeability of plate cylinders (aswell as their size) is the basic difference between flexography andconventional rotary letterpress. It allows the printer to make-ready offpress while running other work; downtime is minimized.

SUMMARY OF THE INVENTION FIG. 1 illustrates in block diagram form thebasic components of the COMPURITE l ink jet printing system. Variabledata information to be printed by the ink jet nozzles in registrationwith fixed form data printed by a plate cylinder are stored in magnetictape unit 30 on two magnetic tapes identified as unit 0 and unit 1. Thevariable data is formatted so that the data therein can be read into,and under the control of, computer 31. Computer 3] assembles thevariable data into an alpha/numeric character message format fordistribution to computer interface 33. Computer 3] has the capability ofreading the magnetic tapes, storing the data thereon and providing thebasic data control and program sequencing functions for formulating thevariable data input to computer interface 33. Computer 31 includes thenecessary input/output system and data bus lines for communicationbetween computer interface 33 and CRT operator control and display 32.

CRT operator control and display 32 comprise at least a CRT display unitfor visually displaying information to a system operator and anassociated keyboard by which the operator may establish a dialog withthe computer for the insertion of necessary data and information toestablish various system parameters necessary for the operation of theCOMPURITE I system. The CRT display also provides the operator withinformation generated by the computer concerning the operation of thesystem.

Forms position and web speed 34 includes the necessary transducers, suchas optical encoders, for providing data relating to the desired formdepth, web speed, and rate of rotation of a master printing cylinder.The web speed and rate of revolution of the master cylinder providenecessary timing pulse inputs to computer interface 33 so that theinterface can provide the necessary timing and control signals forcoordinating the operation of computer 31 and nozzle electronics 35 forprinting the alpha/numeric characters in aligned and registeredrelationship on the moving web.

Computer interface 33 includes the necessary circuitry for receivingtransducer signals from forms position and web speed 34, data controland sequencing information from computer 31, and status signals fromnozzle electronics 35 and nozzles 36 to synchronize and aid incontrolling the operation of the entire COM- PURITE l system. Computerinterface 33 essentially comprises five basic sub-components whichrespectively generate various control and synchronization signals forinternal utilization within the interface itself and for the operationof the nozzle electronics. For reasons which will become more apparentwith the subsequent discussion of the ink droplet formation andprojection of the ink droplets in registered position on a moving web,the speed of which is variable as desired, it is necessary to controlthe time of ink droplet release as a function of web speed. Computerinterface 33 includes Top of Form Controller circuitry for preciselycontrolling the ink droplet release as a function of the web speed andthe top of form of the master plate cylinder. its output, a correctedtop of form pulse (CTOF) represents a basic control signal within theinterface which is used as a reference from which all the characterstrobe and timing signals within the Interface are generated for thesubsequent control of the nozzles within a print unit or print units.The CTOF is also adjusted in accordance with a desired form depth whichis selectable by the operator whereby the variable information printedby the ink jet nozzles can be displaced or registered with respect tovarious form depths on the master cylinder.

Computer interface 33 includes a Master Head Controller for each printunit. The Master Head Controller receives heading distance informationfrom the computer and generates the necessary timing signals to controlthe ink droplet release from the first nozzle in each print unit withwhich the Master Head Controller is associated. These timing signals aregenerated by counting clock pulses having a rate which is variable indirect proportion to the web speed. The operation of the Master HeadController is controlled by the CTOF pulse. The timing signals comprisecharacter strobe pulses (STRl pulses) for providing a reference framewithin which are formed five spaced character stroke strobe pulses (STRZpulses) in which each of the STR2 pulses -times" the release of arespective column of the 5 X 7 matrix from which all of thealpha/numeric charac ters in the COMPURlTE 1 system are generted. TheMaster Head Controller also generates additional timing signals whichprovide control functions to Head Controllers 2, 3, 4 and 5 of itsassociated print unit. The Master Head Controller also generates a printrequest signal, prior to the actual time of droplet release, for thenozzle electronics so that the No. 1 nozzle of that printing unit can beprimed for printing.

Computer interface 33 further includes common Head Controller circuitryfor receiving a device address signal and control functions foroperating the Master Head and Head Controllers 2, 3, 4 and 5 of a printunit. These control functions comprise DISABLE, ENABLE, STOP PHASING,and START PHASING signals as well as a start signal from the computerwhich synchronizes the operation of the Master Head Controllers of eachprint unit as well as the operation of the remaining four HeadControllers for each print unit.

The computer interface 33 further comprises identical circuitry for eachof the second. third, fourth and fifth Head Controllers of each printunit to generate timing signals for controlling the respective dropletrelease from each of the associated nozzles 2, 3, 4 and 5 of that printunit. These timing signals also comprise character strobe pulses (STRlpulses) and character strobe pulses (STRZ pulses) which perform the samefunction as the same named pulses generated by the Master HeadController. However, the character strobe and stroke strobe pulses fromthe respective Head Controllers 2, 3, 4 and 5 are generated to accountfor the displacement along the axis of web movement of the nozzle withina print unit. That displacement is fixed during any given printingoperation, but may be varied within the mechanical limitations of thenozzle structure and the format which is desired to be printed. In otherwords, the spacing between the nozzles along the axis of the moving webmay be varied as well as the respective spacing of the nozzles along anaxis transverse to the axis of web movement. Each of Head Controllers 2,3, 4 and 5 includes suitable circuitry for timing the generation of thecharacter strobe and stroke strobe pulses to account for the spacingbetween the nozzles in the direction of web movement. Each of the headcontrollers includes circuitry for generating a print request signalwhich is delivered to its associated nozzle to prime the associatednozzle for printing.

Head controller circuitry identical to all the head units is providedwithin computer interface 33 to count the number of characters printedby each nozzle so that end of message control signals can be generatedto terminate the generation of the character strobe and stroke strobepulses within the Master Head Controller and Head Controllers 2, 3, 4and 5 of each of the print units as well as to signal the computer thatthe printing of a particular variable set of data has been completed.This circuitry also generates register strobe signals for controllingthe output of coded alpha/numeric character data to the nozzleelectronics.

The nozzles of each print unit are associated with a set of storage andprint buffers which are responsive to respective register strobe signalsfrom the Common Head Controller Circuitry for strobing the characterdata from the computer data bus to a seven line output representing agiven character by a seven bit ASCII code. Each of the nozzlecontrollers includes addressing, sense line, and data control circuitryfor controlling the receipt of information from the computer and forproviding a means of communicating with each of the nozzles whereby thecomputer can determine their respective status for printing.

The printing format of the embodiment disclosed herein includes a lengthof thirty-eight characters in each of the lines of printing. Theembodiment also utilizes a displacement of ten characters per inch ofweb movement. The spacing of the lines between the printing nozzles of agiven print unit and between the print units themselves, is variable andlimited only by the mechanical configuration of the press, the mountingof the mechanical structure of the print units, etc.

Nozzle electronics 35 receives the coded alpha/numeric character dataoutput as well as the character STRl and STRZ pulses of computerinterface 33, whereby the printing of the alpha/numeric characters fromeach of the nozzles within a print unit is controlled. A matrixgenerator for each of the nozzles provides a stream of pulsessynchronized with respect to the generation of ink droplets in thenozzles themselves. The pulse stream is timed by the character strobepulses from the computer interface so that each column of the 5 X 7matrix is timed to release the droplets in registered and alignedrelationship on the moving web regardless of its speed.

The pulse stream output from each matrix generator is converted bydigital-to-analog conversion circuitry, a separate circuit beingresponsive to each of the matrix generators, whereby a low level videoramp signal representing seven different voltage levels for each columnof the matrix is produced. The low level video signals are amplified andprovided as control voltages to a charging tunnel whereby each of thesuccessive drops in the droplet stream projected from each nozzle ischarged in accordance with its desired displacement along an axistransverse to the movement of the web. The video amplifier issynchronized with the excitation of a piezoelectric crystal which formsthe droplets in each of the nozzles so that the droplet charging isproperly phased with the generation of droplets.

Nozzle electronics 35 also includes high voltage deflection circuitryfor placing a static charge on the charging plates of a deflectiontunnel through which each of the charged droplets passes, therebydeflecting each droplet a distance directly proportional to the chargeplaced on each respective droplet during its passage through thecharging tunnel. Uncharged droplets are not deflected and areintercepted by a collector prior to their impingement on the web so thatthey play no part in the printing of the alpha/numeric characters.

The nozzle electronics 35 also includes well-known phasing and dropletsensor circuitry for sensing the phasing of the ink droplets and tocorrect that phasing should it require correction.

Finally, the COMPURITE system includes means for controlling the inksupply and flow of ink to each of the respective nozzles and that systemis designated by numeral 37 in FIG. 1. The print units each include anink supply manifold whereby each of the five nozzles in a print unit areparallelly supplied with ink from ink reservoirs. The uncharged inkdroplets which are intercepted by each of the respective collectorsassociated with each of the nozzles are withdrawn by a manifold vacuumreturn connected to each of the collectors. The

ink system 37 also includes appropriate filters and pressure regulatorsto assure a proper supply of ink to each of the ink jet nozzles.

OBJECTS OF THE INVENTION fixed data information printed on the movingweb by a master press cylinder.

A second object of the invention is to provide such a computerizedprinting system wherein the variable data is printed using ink jetprinting technology wherein all of the alpha/numeric characters of thevariable data are generated from a X 7 character matrix.

It is a third object of the present invention to provide computerinterface circuitry between the computer and ink jet print nozzles forcontrolling the timing of the ink droplets in accordance with variableweb speed.

It is a fourth object of the present invention to provide computerinterface circuitry for controlling the transmission of coded characterdata information from the computer to the nozzle electronics inaccordance with variable web speed and heading distance information fromthe computer.

It is a fifth object of the present invention to provide the necessaryalpha/character timing signals to the nozzle electronics whereby theelectrical signals for defining the character matrix for eachalpha/numeric character are determined so that the alpha/numericcharacters are printed in aligned and registered relationship on themoving web.

It is a sixth object of the invention to provide computer interfacecircuitry wherein the registration and alignment of the printing of thealpha/numeric characters from each of a number of ink jet nozzles isselectively varied in accordance with the form depth of the masterprinting cylinder.

It is a seventh object of the invention to provide computer interfacecircuitry of the type specified herein which is capable ofsimultaneously controlling a plurality of ink jet nozzles wherebyalpha/numeric data is printed from the nozzles in aligned and registeredrelationship with the form depth on a master cylinder.

It is an eighth object of the present invention to provide computerinterface circuitry of the type specified herein for the generation ofcharacter strobe signals which are automatically adjusted in accordancewith the variable speed of a moving web, the selected form depth,heading distance data provided by the computer. and to compensate oraccount for the spacing of the individual printing nozzles with respectto one another along the axis of movement of the web.

It is a ninth object of the present invention to provide computerinterface circuitry of the type specified herein which is responsive toaddress, control commands and data information from a computer whichassembles the variable data in accordance with a given message format,for generating character printing timing signals to time the release ofink droplets from a plurality of ink jet nozzles whereby alpha/numericcharacters may be printed in aligned and registered relationship with amaster printing cylinder over a wide range of press speeds.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 illustrates in block diagram form the components of the COMPURITEI system;

FIG. 2 illustrates the configuration of a print unit illustrating therelationship of the five printing heads thereof and a five-line printoutput with each line being printed by a respective head or nozzle;

FIG. 3 shows an exemplary embodiment of three print units eachconsisting of five staggered heads for respectively printing differentvariable information on different portions of a moving web and alsofiguratively shows the relationship of the print units to a printcylinder for printing a form wherein the variable data are in registeredposition with respect to the plate cylinder;

FIG. 4 shows a representative matrix font consisting of 64 alpha/numericcharacters each of which is configured within a 5 by 7 matrix;

FIGS. 5A and 5B are circuit schematics of the interface top of formcontroller;

FIG. 6 is a schematic representing the interface head controllers commoncomputer address circuitry;

FIG. 7 is a schematic of an interface master head controller;

FIG. 8 illustrates a schematic of interface head controllers 2, 3, 4 and5;

FIG. 9 is a schematic representative of the interface head controllerscommon end of message circuitry;

FIG. 10 represents the circuit schematic for common interface nozzlecontroller circuitry;

FIGS. 11A and 118 respectively show gating circuitry used in thecomputer interface;

FIG. 12 shows the operative relationship between the interfaceschematics represented by FIGS. 5A, 5B and 6 to 10;

FIG. 13 is a side view of the plate cylinder showing the form depths andthe encoder slits used in timing the print nozzles;

FIG. 14 illustrates the relationship of various control signals of thecomputer interface as a function of a given press speed;

FIG. 15 is a combined block diagram and functional representationrespectively of the nozzle electronics and an ink jet nozzle showing theinterrelationships between the electrical signals for operating thenozzle and the relationship of the ink droplet stream with respect tothe elements of the nozzle and the moving web;

FIGS. 16A through illustrate the principle of operation of the nozzleelectronics;

FIG. 17 shows the ink supply manifold and vacuum manifold assembly for afive-nozzle print unit which forms part of the ink system; and

FIG. 18 is an illustrative embodiment of the ink supply regulatorforming part of the ink system.

DETAILED DESCRIPTION FIG. 2 illustrates a typical print unit 38 of theCOM- PURITE l system in operative association with a moving web 39. Eachof the five ink jet nozzles 38a, 38b. 38c, 38d and 38e of print unit 38is mounted to print a respective line of print 40a, 40b, 40c. 40d, and40e. As illustrated in FIG. 2, each of the print lines 40a to 40e areequally spaced from one another; however, the interline spacing may bevaried by suitably adjusting the mounting of a desired one or all of inknozzles 38a to 38a in a direction transverse to the movement of web 39.In the COMPURITE system described herein, each of nozzles 38a to 38e isspaced a distance D from an adjacent nozzle in a print unit 38. Thedistance D is two and one-half inches for the system as describedherein. However, such a mounting relationship of the respective nozzleswithin a print unit is only exemplary, and it is understood that thespacing D between each nozzle may be varied if desired by a suitablemodification of the interface circuitry as will be apparent from thedesription herein of its structure and operation.

In an operative embodiment and in actual use, the ink jet nozzles of theCOMPURITE l system lie in a horizontal plane with the moving web 39moving in a vertical plane. However. the positions of the print unit andthe moving web in the horizontal and vertical planes may beinterchanged, if it is recognized that poor results are obtained whenthe ink jet nozzles are required to emit their droplets against theforce of gravity. Each of the ink jet nozzles 38a to 38:2 lies in aplane normal to the plane of moving web 39.

FIG. 3 illustrates a three-print unit ink jet printing system comprisingprint units 38, 38' and 38". Each of the print units 38, 38 and 38"includes five ink jet nozzles respectively designated as 38a to 38e, 38'to 38e' and 38a to 38:2". Moving web 39 is illustratively driven bydrive rollers 41a, 41b in the vertical direction indicated in FIG. 3.The mounting structure for each of print units 38, 38' and 38" is notshown in FIG. 3 to avoid cluttering the drawing. The print units may bemounted by any suitable mounting structure so that they are in properspaced relationship to moving web Continuing with FIG. 3, master printcylinder 40 is illustratively shown in operative relationship with printand drive roller 41a. However, the relationship of print cylinder 40 toprint roller 41a and print units 38, 38'. 38 is only exemplary. Masterprint cylinder 40 may be located further downstream from the moving web39 than is depicted in FIG. 3. It is also understood that master printcylinder 40 may be located upstream of print units 38, 38, 38". Themechanical top of form of master print cylinder 40 is illustrated inFIG. 3. Displaced from the mechanical top of form is a slit 4] fromwhich electrical top of form pulses may be produced by suitable opticalencoder circuitry which is well known to those skilled in the art. Anumber of slits 42 are provided around the periphery of master printcylinder 40 to generate a fixed number of timing pulses for eachrevolution of the master cylinder. In the embodiment described hereinthere are 2500 slits 42. Suitable electrical pulses are generated byoptical encoder mechanism associated with slits 42. The electrical topof form pulse as well as the 2500 pulses per revolution of printcylinder 40 are inputs to the interface circuitry to provide thenecessary timing functions for the operation of that circuitry.Additionally, a transducer is provided to generate clock pulses for theInterface at a fixed number of pulses/inch of web travel. Such atransducer is not shown in FIG. 3, but may comprise any well-known speedtransducer such as is normally used with the drive and gear trainmechanism of printing presses to indicate its speed.

The spacing between print units 38, 38' and 38" can be varied to provideany desired variable data printing format on the forms printed by themaster cylinder. It is also understood that the lateral spacing of printunits 38, 38' and 38" can also be adjusted as desired in a directiontransverse to the movement of web 39, whereby the printing from each ofthe respective print units in relationship to the form or forms onmaster plate cylinder can be adjusted as desired.

With each of print units 38, 38' and 38" mounted in a fixed spatialrelationship with the master print cylinder 40, the COMPURITE I systemincludes form depth selection by the operator and the COMPURITEinterface circuitry automatically adjusts the generation of thecharacter strobe pulses to cause the ink jet printing to be registeredand aligned in accordance with the form depth selected.

FIG. 4 illustrates an exemplary alpha/numeric matrix font comprising atotal of sixty-four alpha/numeric characters. As is evident from FIG. 4,each of the alpha/numeric characters is generated by a 5 X 7 matrix aswill be more clearly understood from the description which follows. Eachink jet nozzle is capable of producing each of the sixty-fouralpha/numeric characters illustrated in FIG. 4. It is understood thatthe character font in FIG. 4 is only exemplary and that other type fontsmay also be used with the COMPURITE I system described herein.

THE COMPUTER HARDWARE, SOFTWARE, FUNCTIONS AND OPERATIONS As theCOMPURITE I system is described herein, the variable information (e.g.,mailing addresses) to be printed on a form must be recorded on an inputdevice such as a magnetic tape, paper tape, card, etc. It is understoodthat if the input, for example the information stored on magnetic tape,is not compatible with the COMPURITE requirements as described herein,the data may be converted from the customers tape format to theCOMPURITE format by any of the well-known conversion techniques. Inorder to make such a conversion it is necessary to know the recordlayout of the magnetic tape to be converted. It is also imperative toknow precisely what information is required to be printed, where it islocated on the tape, and the required format of the COMPURITE printing.

For the purposes of the present description the alpha/numeric charactersare set in ASCII (American Standard Code for Information Interchange).Table I defines the ASCII character set for the 64 character fontdescribed herein.

TABLE I ASCII Character Set BITS I o 0 0 0 0 0 Space P o 0 0 I I A 0 o 0I 0 2 a R 0 0 1 I 3 c s o 1 0 0 s 4 D T U I 0 l 7: S E U U I l 0 & 6 F V0 l I I 7 G W I 0 0 0 s H x 1 o 0 I I a I Y I 0 I 0 1 .I z I O I K I l 00 L I 0 l M I I I O N I I I I

1. A printing system wherein variable alpha/numeric data is printed inregistered and aligned relationship with fixed data printed by a masterplate cylinder on a moving web at press speeds, comprising: means forproviding coded data representative of said variable data in a selectedmultiple line message format and for providing command signals; controlmeans for receiving said coded data and responsive to said commandsignals for generating character timing signals representing thesequential position of said alpha/numeric data in said multiple linemessage format, and including means for automatically adjusting saidcharacter timing signals to account for different web speeds andvariable form depth data, said means for automatically adjusting saidcharacter timing signals includes means for generating a top of formpulse for each revolution of said master cylinder, said top of formpulse occurring prior to the mechanical top of form of said mastercylinder, means for generating first pulses having a pulse ratedependent on the speed of the web, and means for correcting said top ofform pulse in accordance with said first pulses, said means forautomatically adjusting said character timing signals being responsiveto said corrected top of form pulse; and means for printing saidvariable data in response to said character timing signals by theprojection of independently controlled ink droplet streams onto saidmoving web.
 2. A printing system as in claim 1 wherein said controlmeans includes means for establishing a number of different mastercylinder form depths and said means for automatically adjusting saidcharacter timing signals includes switching means for correcting saidtop of form pulse in accordance wIth a desired one of said form depths.3. A printing system as in claim 2 wherein said means for automaticallyadjusting said character timing signals further includes means forcounting pulses including a first counter for counting said firstpulses, means for controlling said first counter to count for a fixedperiod of time and said means for correcting said top of form pulseincludes a counter for storing the count in said first counter andcounting said first pulses until a predetermined count is reached andgenerating a signal representing said corrected top of form pulse.
 4. Aprinting system as in claim 3 wherein said means for controlling saidfirst counter comprises a third counter and means for generating secondpulses at a fixed rate, said third counter establishing a periodicsampling for the operation of said first counter.
 5. A printing systemas in claim 3 wherein said control means further includes pulsegenerating means for generating second pulses having a fixed number ofpulses per revolution of said master cylinder and said means forautomatically adjusting said character timing signals further includessecond counter means for counting said second pulses, number decodingmeans for determining the number of pulses corresponding to said numberof form depths and gate means for gating the number of decoded pulses tosaid switching means in response to said top of form pulse, saidswitching means delaying the initiation of said second counter means inaccordance with a desired form depth.
 6. A printing system as in claim 5wherein said means for establishing a number of different mastercylinder form depths further includes means for inhibiting to establisha correct phasing when a form depth of two is selected.
 7. A printingsystem as in claim 1 wherein said means for printing includes at leastone printing unit including a number of ink-jet nozzles mounted instaggered relationship along an axis parallel to the movement of saidweb and each independently controlling the release of an ink dropletstream, and said control means further includes a master controller anda number of slave controllers for controlling said at least one printingunit, said master controller controls that ink-jet nozzle firstconfronting selective printing areas on said moving web and said slavecontrollers each control a selected one of said remaining ink-jetnozzles, said master controller is responsive to said corrected top ofform pulse for generating signals controlling the release of inkdroplets from the associated ink-jet nozzle and secondary timingsignals, one of said slave controllers generating tertiary timingsignals controlling the release of ink-droplets from the associatedink-jet nozzles and for controlling another of said slave controllers,whereby said slave controllers generate signals for controlling therelease of ink droplets from an associated ink-jet nozzle and additionaltiming signals for controlling that slave controller associated with asuccessively displaced one of said ink jet nozzles.
 8. A printing systemas in claim 7 wherein said means for providing coded data includesbuffer and print storage means for storing successive alpha/numericcharacters within said multiple line message format and means forgenerating shift pulses from said corrected top of form pulse to shiftdata from said buffer register to said print register and to store newdata in said buffer register, and said means for printing beingresponsive to the output from said print register.
 9. A printing systemas in claim 7 wherein said signals from said master and slavecontrollers for controlling the release of ink droplets each includeprimary pulses having a pulse rate determined at least partially by thespeed of said moving web and secondary pulses spaced between saidprimary pulses, said primary pulses denoting successive alpha/numericcharacters and said secondary pulses controlling an ink-droplet streamfrom the associated ink-jet nozzle.
 10. A printing system as in claim 9wherein said master controller includes counting means for receivingheading distance information from said means for providing coded data,means for gating said first pulses to said counting means fordecrementing said counting means, and means responsive to thedecrementing of said counting means to zero to produce an artificialstrobe pulse for initiating the generation of said secondary timingsignals.
 11. A printing system as in claim 10 wherein said mastercontroller further includes means for dividing said first pulses andfirst gating means responsive to the output of said dividing means togenerate said primary pulses and second gating means responsive to theoutput of said dividing means for generating said secondary pulses. 12.A printing system as in claim 9 wherein said slave controllers eachincludes counting means, and means for gating said first pulses to saidcounting means and means responsive to said counting means attaining apredetermined count representative of said staggered relationshipbetween said ink-jet nozzles for generating an artificial strobe pulsefor initiating the generation of said additional timing signals.
 13. Aprinting system as in claim 12 wherein each of said slave controllersfurther includes means for dividing said first pulses and first gatingmeans responsive to the output of said dividing means to generate saidprimary pulses and second gating means responsive to the output of saiddividing means for generating said seconary pulses.
 14. A printingsystem as in claim 9 wherein said control means further includes meansfor determining the number of characters printed by each of said ink jetnozzles and being responsive to said primary and secondary pulses fromeach of said master and slave controllers and wherein said means forproviding coded data further includes means for temporarily storingcoded data representative of said variable data and responsive to saidmeans for determining the number of characters printed to transmit saidcoded data to said means for printing.
 15. A printing system as in claim14 wherein said means for temporarily storing said coded data comprisespaired sets of storage and print buffer circuitry each respectivelystoring two characters whereby the coded data representative of said twostored characters is successively gated from said storage buffer to saidprint buffer and to said means for printing by said means fordetermining said number of characters printed.
 16. A printing system asin claim 9 wherein said control means further includes means responsiveto said primary and secondary pulses from each of said master and slavecontrollers for determining the end of said selected multiple linemessage format and wherein said master and slave controllers are eachresponsive to an associated one of said end of message signals forterminating the generation of said primary and secondary pulses.
 17. Amethod for printing variable alpha/numeric data in registered andaligned relationship with fixed data printed by a master plate cylinderon a moving web at press speeds, comprising the steps of: providingcoded data representative of the variable data in a selected multipleline message format and providing command signals; generating charactertiming signals in response to said command signals representing thesequential position of said alpha/numeric data in said multiple linemessage format; generating a top of form pulse for each revolution ofsaid master cylinder prior to the mechanical top of form of said mastercylinder; generating first pulses having a pulse rate dependent on thespeed of the web; correcting said top of form pulse in accordance withsaid first pulses; automatically adjusting said character timing signalsto account for different web speeds and variable form depth data inaccordance with said corrected top of form pulse; and printing saidvariable data in response to said character timing signals by projectingindependently controlled ink droplet streams onto said moving web.
 18. Amethod as in claim 17 further including the step of establishing anumber of different master cylinder form depths and said step ofautomatically adjusting the character timing signals includes correctingthe top of form pulse in accordance with a desired one of said formdepths.
 19. A method as in claim 17 further comprising the step ofgenerating a plurality of primary pulse trains, each train having apulse rate determined at least partially by the speed of the moving weband a plurality of secondary pulse trains, each train spaced between arespective different one of said primary pulse trains, said primarypulse trains each denoting successive alpha/numeric characters and saidsecondary pulse trains each controlling a respective ink droplet stream.